Fan apparatus

ABSTRACT

A fan apparatus includes first axial fans each arranged with a rotation axis thereof extending perpendicularly or substantially perpendicularly to a mounting surface provided in a case designed to contain an electronic device; and second axial fans each having a rotation axis coinciding with the rotation axis of a separate one of the first axial fans. The first axial fans are arranged to rotate in a first rotation direction to introduce, send, or discharge air into, inside, or out of the case, while the second axial fans are arranged to rotate in a second rotation direction opposite to the first rotation direction to cause a flow of air in the same direction in which the first axial fans cause a flow of air. Both of the first axial fans and the second axial fans either share a common single-piece housing or have separate housings joined together.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a fan apparatus. More specifically, the present invention relates to a fan apparatus that is arranged to be attached to a case designed to contain an electronic device.

2. Description of the Related Art

A variety of conventional fan apparatuses including a plurality of fans have been provided to be attached to cases designed to contain electronic devices. JP-A 2008-140406, for example, discloses a conventional rack-mounted system 10 including fan/LAN tray slots 23. Each fan/LAN tray slot 23 is provided with eight air blowers, as shown in FIG. 8 of JP-A 2008-140406.

JP-A 2008-251067 discloses another conventional fan apparatus included in a power supply module 40 used for a disk array apparatus, as shown in FIG. 14 of JP-A 2008-251067. In a fan portion 42 of the power supply module 40, two fans 43 having the same structure are arranged in tandem, one in front of the other, along an axial direction.

SUMMARY OF THE INVENTION

With improved performance and increased density of electronic devices, cases designed to contain such electronic devices are required to have improved ventilation efficiency. Accordingly, preferred embodiments of the present invention provide a fan apparatus that enables air to be efficiently introduced into, sent inside, or discharged out of such a case.

A fan apparatus according to a preferred embodiment of the present invention includes a plurality of first axial fans arranged in a two-dimensional array in parallel or substantially in parallel to a mounting surface provided in a case designed to contain an electronic device, each of the first axial fans having a rotation axis perpendicular or substantially perpendicular to the mounting surface; and a plurality of second axial fans arranged in a two-dimensional array in parallel or substantially in parallel to the mounting surface, each having a rotation axis coinciding with the rotation axis of a separate one of the first axial fans, and being arranged in contact or close proximity with the separate one of the first axial fans. The first axial fans are preferably arranged to rotate in a first rotation direction to introduce air into the case, discharge air out of the case, or send air inside the case, while the second axial fans are arranged to rotate in a second rotation direction opposite to the first rotation direction to cause a flow of air in a same direction in which the first axial fans cause a flow of air. The first axial fans preferably either share a common single-piece housing or have separate housings joined together, and the second axial fans either share a common single-piece housing or have separate housings joined together.

The fan apparatus according to preferred embodiments of the present invention enables air to be efficiently introduced into, sent inside, or discharged out of the case designed to contain the electronic device.

Fan apparatuses according to preferred embodiments of the present invention are usable as fan apparatuses to be attached to a variety of cases designed to contain electronic devices.

The above and other elements, features, steps, characteristics and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments with reference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of a rack-type electronic system according to a first preferred embodiment of the present invention.

FIG. 2 is a right side view of the rack-type electronic system.

FIG. 3 is a plan view of a first fan tray according to the first preferred embodiment of the present invention.

FIG. 4 is a plan view of a second fan tray according to the first preferred embodiment of the present invention.

FIG. 5 is a plan view of an example modification of the first fan tray.

FIG. 6 is a front view of a rack-type electronic system according to a second preferred embodiment of the present invention.

FIG. 7 is a right side view of the rack-type electronic system according to the second preferred embodiment of the present invention.

FIG. 8 is a partial cross-sectional view of a contra-rotating fan according to the second preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Preferred Embodiment

FIG. 1 is a front view of a rack-type electronic system 1 according to a first preferred embodiment of the present invention. FIG. 2 is a right side view of the rack-type electronic system 1. The rack-type electronic system 1 preferably includes a case 11, electronic devices 12, power supply units 13, first fan trays 14, and second fan trays 15.

The exterior of the case 11 is preferably rectangular parallelepiped shaped, but could be any other desirable shape is so desired. The case 11 contains the electronic devices 12, the power supply units 13, the first fan trays 14, and the second fan trays 15. The electronic devices 12 in this preferred embodiment are so-called blade servers, which are substantially plate-shaped, but any other type of electrical device could be included without departing from the present invention. The electronic devices 12 are preferably arranged horizontally and in an upright orientation. Preferably three arrays of the electronic devices 12 are provided at different vertical levels. As illustrated in FIG. 2, the power supply units 13 are arranged behind the arrays of the electronic devices 12. Other components, such as a control device, a communication device, and the like, are arranged near the power supply units 13 as appropriate.

In this preferred embodiment, four pairs of the first and second fan trays 14 and 15 are arranged above or below the arrays of the electronic devices 12, but any other number of the first and second fan trays 14 and 15 could be provided if so desired. Each second fan tray 15 is placed above the paired first fan tray 14. In other words, each pair of the first and second fan trays 14 and 15 defines an individual fan apparatus 10. Four of such fan apparatuses 10 are arranged at different locations in the rack-type electronic system 1. As illustrated in FIG. 2, each of the first and second fan trays 14 and 15 is capable of being horizontally inserted into and removed from the case 11 through a front of the case 11.

FIG. 3 is a plan view of the first fan tray 14. A bottom side of FIG. 3 corresponds to the front of the case 11. A total of twelve first axial fans 2, three in a width direction and four in a depth direction, are arranged on the first fan tray 14 is preferably provided. Each first axial fan 2 includes a motor, an impeller 21, and a housing 22. A rotation axis J2 of the first axial fan 2 extends in a vertical direction. The motor is preferably a direct current brushless motor, but any other desirable type of motor could be used. The impeller 21 includes a central cup portion 211 and a plurality of blades 212. The blades 212 are arranged to project radially outward from an outside surface of the cup portion 211. The motor is placed inside the cup portion 211. The housing 22 is arranged to surround an outer circumference of the impeller 21. In FIG. 3, the impeller 21 is preferably arranged to rotate counterclockwise as indicated by arrow R2.

FIG. 4 is a plan view of the second fan tray 15. A bottom side of FIG. 4 corresponds to the front of the case 11. A total of twelve second axial fans 3, three in the width direction and four in the depth direction, are arranged on the second fan tray 15. The second fan tray 15 is similar in structure to the first fan tray 14 except that the second axial fans 3 are arranged to rotate in an opposite direction. That is, each second axial fan 3 includes a motor, an impeller 31, and a housing 32. A rotation axis J3 of the second axial fan 3 extends in the vertical direction. In FIG. 4, the impeller 31 is arranged to rotate clockwise as indicated by arrow R3. The impeller 31 includes a central cup portion 311 and a plurality of blades 312.

In the case where a frame 141 of the first fan tray 14 is regarded as a horizontal mounting surface for the first axial fans 2 provided in the case 11, the first axial fans 2 are arranged in a two-dimensional array in parallel or substantially in parallel to the mounting surface, with the rotation axis J2 of each of the first axial fans 2 extending perpendicularly or substantially perpendicularly to the mounting surface. Similarly, in the case where a frame 151 of the second fan tray 15 is regarded as a horizontal mounting surface for the second axial fans 3 provided in the case 11, the second axial fans 3 are arranged in a two-dimensional array in parallel or substantially in parallel to the mounting surface, with the rotation axis J3 of each of the second axial fans 3 extending perpendicularly or substantially perpendicularly to the mounting surface. The first and second fan trays 14 and 15 are placed one above the other such that the rotation axes J2 of the first axial fans 2 and the rotation axes J3 of the second axial fans 3 coincide with each other. In addition, the array of the first axial fans 2 and the array of the second axial fans 3 are arranged in contact or close proximity with each other along an axial direction.

A situation in which the array of the first axial fans and the array of the second axial fans 3 are arranged in contact or close proximity with each other means a situation in which a rotational velocity component of an air flow from each axial fan on an inlet side serves to increase efficiency of the associated axial fan on an outlet side in sending out the air, and encompasses a situation in which the fan trays placed one above the other have been fitted into the case 11, with the result that the array of the first axial fans 2 and the array of the second axial fans 3 are spaced from each other. The array of the first axial fans 2 and the array of the second axial fans 3 may be spaced from each other by a greater distance so long as the aforementioned interaction therebetween can still be achieved.

The housing 22 of each first axial fan 2 is attached to the frame 141 of the first fan tray 14, so that the first axial fans 2 are, in essence, joined together horizontally. Similarly, the housing 32 of each second axial fan 3 is attached to the frame 151, so that the second axial fans 3 are, in essence, joined together horizontally. As a result, as described above with reference to FIG. 2, the array of the first axial fans 2 is capable of being inserted into and removed from the case 11 in the direction parallel or substantially parallel to the mounting surface. Similarly, the array of the second axial fans 3 is capable of being inserted into and removed from the case 11 in the direction parallel or substantially parallel to the mounting surface.

Each first axial fan 2 is arranged to cause an upward flow of air through the counterclockwise rotation of the impeller 21. Each second axial fan 3 is arranged to cause the same upward flow of air through the clockwise rotation of the impeller 31. The case 11 has openings on top and bottom portions thereof. The lowermost fan apparatus 10 is arranged to introduce air into the case 11 through the bottom portion of the case 11. The second and third fan apparatuses 10 from the bottom are arranged to send the air inside the case 11 so that the air travels further upward. Finally, the uppermost fan apparatus 10 is arranged to discharge the air out of the case 11.

In the rack-type electronic system 1, the first axial fans 2 and the second axial fans 3, which are arranged to rotate in mutually opposite directions with respect to one another, are arranged along the axial direction to achieve an improvement in static pressure-air volume characteristics of the fan apparatuses 10. This enables air to be efficiently introduced into, sent inside, and discharged out of the case 11, which contains the electronic devices arranged in a densely packed manner. Moreover, it is possible to reduce a production cost of the fan apparatuses 10 through the similarity between the frame 141, which is a component used to join the first axial fans 2 together, and the frame 151, which is a component used to join the second axial fans 3 together.

FIG. 5 is a plan view of an example of a modification that can be made to the first fan tray 14. In this modification of the first fan tray 14, a single-piece housing 22 a serves as a common housing of all the first axial fans 2. In the other respects, this modification of the first fan tray 14 is similar to the first fan tray 14 illustrated in FIG. 3. Similarly, in a modification of the second fan tray 15, a single-piece housing may be arranged to serve as a common housing of all the second axial fans 3.

Second Preferred Embodiment

FIG. 6 is a front view of a rack-type electronic system la according to a second preferred embodiment of the present invention. FIG. 7 is a right side view of the rack-type electronic system 1 a. The rack-type electronic system la includes the case 11, the electronic devices 12, the power supply units 13, and fan trays 16. The rack-type electronic system la is similar to the rack-type electronic system 1 illustrated in FIGS. 1 and 2 except that each fan tray 16 replaces a separate pair of the first and second fan trays 14. That is, each fan tray 16 in the rack-type electronic system 1 a corresponds to a separate one of the fan apparatuses 10 illustrated in FIG. 1. In the other respects, the rack-type electronic system 1 a is similar to the rack-type electronic system 1, and in the following description, components that have their counterparts in FIGS. 1 and 2 are assigned the same reference numerals as in FIGS. 1 and 2.

In each fan tray 16, a plurality of first axial fans 2 are arranged to define a lower array, and a plurality of second axial fans 3 are arranged to define an upper array. The manners of the horizontal arrangement of the first axial fans 2 and of the second axial fans 3 are similar to those illustrated in FIGS. 3 and 4, respectively. In the fan tray 16, the housing 22 of each first axial fan 2 and the housing 32 of the associated second axial fan 3 are joined together in the vertical direction to provide a so-called contra-rotating fan 4.

FIG. 8 is a partial cross-sectional view of the contra-rotating fan 4. The first axial fan 2 includes a motor 23, the impeller 21, and the housing 22. Note that the relative vertical positions of the impeller and the motor are reversed compared to those in the first axial fan 2 illustrated in FIG. 3, and that the impeller 21 is arranged below the motor 23. The second axial fan 3 includes a motor 33, the impeller 31, and the housing 32. In FIG. 8, a mechanism to join the housings 23 and to each other is omitted from illustration. The contra-rotating fan 4 includes a rib 24 arranged to support the motor in relation to the housing 22, and a rib 34 arranged to support the motor 33 in relation to the housing 32. The ribs 24 and 34 are arranged one above the other and in contact or close proximity with each other.

Also in the fan tray 16, the rotation axes J2 of the first axial fans 2 and the rotation axes J3 of the second axial fans 3 are arranged to coincide with each other such that they are coaxial or substantially coaxial. Each of the first axial fans 2 and the associated one of the second axial fans 3 are arranged in contact or close proximity with each other along the axial direction. The impeller 21 of each first axial fan 2 is arranged to rotate counterclockwise in plan view to cause an upward flow of air. The impeller 31 of each second axial fan 3 is arranged to rotate clockwise in plan view to cause the same upward flow of air.

In the case where a frame 161 of each fan tray 16 is regarded as a horizontal mounting surface for the first axial fans 2 provided in the case 11, the first axial fans 2 are arranged in a two-dimensional array in parallel or substantially parallel to the mounting surface, with the rotation axis J2 of each of the first axial fans 2 extending perpendicularly or substantially perpendicularly to the mounting surface. The second axial fans 3 are also arranged in a two-dimensional array in parallel or substantially parallel to the mounting surface, with the rotation axis J3 of each of the second axial fans 3 extending perpendicularly or substantially perpendicularly to the mounting surface.

The assembly of each of the first axial fans 2 and the associated one of the second axial fans 3 is attached to the frame 161, so that the assemblies of the first axial fans 2 and their respective associated second axial fans 3 are, in essence, joined together horizontally, resulting in a unified collection of the first and second axial fans 2 and 3 as illustrated in FIG. 7. The unified collection is capable of being inserted into and removed from the case 11 in the direction parallel or substantially parallel to the mounting surface.

In the rack-type electronic system la, the lowermost fan tray 16 is arranged to introduce air into the case 11 through the bottom portion of the case 11. The second and third fan trays 16 from the bottom are arranged to send the air inside the case 11 so that the air travels further upward. Finally, the uppermost fan tray 16 is arranged to discharge the air out of the case 11.

The rack-type electronic system la is also so constructed as to enable air to be efficiently introduced into, sent inside, and discharged out of the case 11, which contains the electronic devices arranged densely. Moreover, because each contra-rotating fan 4 defines a unit in each fan tray 16, it is possible to reduce a production cost of the fan trays 16.

Other Preferred Embodiments

Note that the present invention is not limited to the above-described preferred embodiments, and that variations and modifications are possible. For example, in a modification of the fan tray 16 according to the second preferred embodiment, a single-piece housing may be arranged to replace the two housings and 32. Also, in modifications of the first and second preferred embodiments, the joining of the housings in directions perpendicular or substantially perpendicular to the axial direction may be accomplished directly through the housings themselves, instead of through the frame of the fan tray.

In modifications of the first and second preferred embodiments, the relative vertical positions of the motor and the impeller in each of the first and second axial fans 2 and 3 may be varied as appropriate. Furthermore, the joining of the housings in the directions perpendicular or substantially perpendicular to the axial direction may be accomplished through an additional joining member provided on sides of the housings, for example.

The mounting surfaces to which the first or second axial fans 2 or 3 are attached may be provided not only inside the case 11 but also on an outer surface of the case 11, in other preferred embodiments. Furthermore, the mounting surfaces may not necessarily be arranged horizontally, but may be arranged, for example, vertically in other preferred embodiments. Furthermore, the first and second axial fans 2 and 3 may be indirectly attached to the mounting surfaces therefor in the case 11 in other preferred embodiments. Furthermore, fan apparatuses according to other preferred embodiments may be used to perform only one of the steps of the introduction of air into the case, the discharge of air out of the case, and the sending of air inside the case. In other preferred embodiments, the case may contain any of a variety of electronic devices, and also a portion of any of the electronic devices may define a portion of the case. The electronic devices contained in the case may be personal computers, disk drive apparatuses, or the like in other preferred embodiments. That is, fan apparatuses according to other preferred embodiments of the present invention may not necessarily be of a tray type. Furthermore, the electronic devices contained in the case may include an electronic device, e.g., a power supply or a light source, which defines a portion of an electronic device system in other preferred embodiments of the present invention.

While preferred embodiments of the present invention have been described above, it is to be understood that variations and modifications will be apparent to those skilled in the art without departing the scope and spirit of the present invention. The scope of the present invention, therefore, is to be determined solely by the following claims. 

1. A fan apparatus comprising: a plurality of first axial fans arranged in a two-dimensional array in parallel or substantially in parallel to a mounting surface provided in a case designed to contain an electronic device, each of the first axial fans having a rotation axis that is perpendicular or substantially perpendicular to the mounting surface; and a plurality of second axial fans arranged in a two-dimensional array in parallel or substantially in parallel to the mounting surface, each having a rotation axis coinciding with the rotation axis of a separate one of the first axial fans, and being arranged in contact or close proximity with the separate one of the first axial fans; wherein the first axial fans are arranged to rotate in a first rotation direction to introduce air into the case, discharge air out of the case, or send air inside the case, while the second axial fans are arranged to rotate in a second rotation direction opposite to the first rotation direction to cause a flow of air in a same direction in which the first axial fans cause a flow of air; and the first axial fans either share a common single-piece housing or have separate housings joined together, and the second axial fans either share a common single-piece housing or have separate housings joined together.
 2. The fan apparatus according to claim 1, wherein the array of the first axial fans is arranged to be capable of being inserted into and removed from the case in a direction parallel or substantially parallel to the mounting surface, and the array of the second axial fans is also arranged to be capable of being inserted into and removed from the case in the same direction.
 3. A fan apparatus comprising: a plurality of first axial fans arranged in a two-dimensional array in parallel or substantially in parallel to a mounting surface provided in a case designed to contain an electronic device, each of the first axial fans having a rotation axis perpendicular or substantially perpendicular to the mounting surface; and a plurality of second axial fans arranged in a two-dimensional array in parallel or substantially in parallel to the mounting surface, each having a rotation axis coinciding with the rotation axis of a separate one of the first axial fans, and being arranged in contact or close proximity with the separate one of the first axial fans; wherein the first axial fans are arranged to rotate in a first rotation direction to introduce air into the case, discharge air out of the case, or send air inside the case, while the second axial fans are arranged to rotate in a second rotation direction opposite to the first rotation direction to cause a flow of air in a same direction in which the first axial fans cause a flow of air; each of the second axial fans and the separate one of the first axial fans arranged in contact or close proximity with the second axial fan either share a common single-piece housing or have separate housings joined together; and a unified collection of the first and second axial fans is arranged to be capable of being inserted into and removed from the case in a direction parallel or substantially parallel to the mounting surface. 